A tax file number (TFN) is a unique nine-digit number we issue to individuals and organisations to help us administer tax and other Australian Government systems.
We only issue one TFN to you during your lifetime, even if you change your circumstances and If you change your name or address, you should tell us so we can update your details.
If you already have a TFN but you don’t know where it is, you may have documents that contain it, such as a notice of assessment or a payment summary from your employer. Alternatively, if you use a registered tax agent, they can tell you your TFN.
There are a number of situations where you will be asked to provide your TFN, such as when you start work or change jobs, apply for income assistance or join a superannuation fund. You should keep it secure and only disclose it to certain individuals or organisations for tax-related purposes.
Most secondary school students are able to get a TFN through the secondary schools TFN program. This is an easier way to apply because you don’t have to provide us with any documents to prove your identity – the school identifies you.
If you operate a partnership, trust or company and want to know how to apply for a TFN, refer to Tax basics for small business or visit the Australian business register website at www.abr.gov.au to apply for an Australian business number (ABN) and TFN.